The broad objective of this project is to understand the biology of serum hormone binding proteins and the role that they play in various human disease states. Future directions project will emphasize delineting the role of steroid binding proteins (corticosteroid-binding globulin and testosterone-binding globulin) and thyroxine-binding globulin in hormonal action in various tissues and elucidating pharmacological and pathological factors modulating the levels of the binding globulins. Continued effort will be placed on establishing a laboratory model for human transport physiology with which the roles of transport proteins in steroid action, metabolism, and pituitary regulation can be investigated.